Nucleic Acids

Which of these segments could be used to correctly complete the DNA molecule in the diagram above?

• F

• G

• H

• J

The triplet code of bases for RNA may be represented by all of the following except —

• CGU

• CGA

• CGT

• CGG

The picture shows an x-ray diffraction of DNA. The x-ray diffraction of DNA led to the idea that DNA —

• can copy itself

• contains paired bases

• is a double helix

• is a very long molecule

The parts of DNA that provide the code for proteins are the —

• phosphates

• sugars

• nitrogenous bases

• hydrogen bonds

Which of these will complete the mRNA strand matched to DNA?

• GUC

• UAC

• AUG

• CAG

The process of DNA replication is necessary before a cell —

• makes a protein

• modifies lysosome enzymes

• codes for RNA molecules

• divides into two cells

The picture shows a segment of DNA from a cat. Which of these is most likely the kitten of this cat?

• 1

• 2

• 3

• 4

If 15% of a DNA sample is made up of thymine, what percentage of the sample is made up of cytosine?

• 15%

• 35%

• 70%

• 85%

In a DNA sample, 20% of the bases are thymine. What percentage of the bases in this sample are adenine?

• 20%

• 40%

• 60%

• 80%

What is the backbone of DNA made up of?

• Sugar and a phosphate group

• Fatty acids and glucose

• Nitrogenous bases

• Sugar and a fatty acid